In gssd/context_lucid.c, ensure that gss_buffer_desc and gss_OID_desc
are defined before write_bytes.h, which uses these definitions, is
included. With TI-RPC, these definitions are not provided by
rpc/rpc.h.

It appears that <gssapi/gssapi_krb5.h> already includes krb5.h and
gssapi.h (on my system, anyway) so let's drop those includes.

Ideally write_bytes.h itself should include the needed headers, but
some source files that use Heimdal include a different, Heimdal-
compatible, header to get these definitions.

The printf format string in nfs_pp_debug() assumes the @program and
@version arguments are unsigned long, because the legacy RPC headers
define both rpcprog_t and rpcvers_t as unsigned long types.

However, the TI-RPC headers define both types as uint32_t, which
requires a different printf format type. If we replace the legacy
headers with TI-RPC headers, this type mismatch generates compiler
warnings that are nothing but noise.

We are about to provide a switch at ./configure time to allow the use
of either the legacy RPC headers or the TI-RPC headers, so we need
a printf format that works in both cases.

To squelch the compiler warnings that occur when using the TI-RPC
headers, cast both arguments in the fprintf statement to the widest of
the two types ("unsigned long" or "uint32_t").

TI-RPC's version of the svc_getcaller() macro points to a sockaddr_in6,
not a sockaddr_in, though for AF_INET callers, an AF_INET address
resides there. To squelch compiler warnings when the TI-RPC version of
the svc_req structure is used, add inline helpers with appropriate
type casting.

General clean up. Removed unused routines. Reworked syslog
message to (hopefully) make it more sensible. Move
"#ifdef HAVE_LIBWRAP" around so nothing will be defined
when tcp wrapper is not configured.

There were some problems with exportfs and rpc.mountd for long export
lists - see https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=76643
I do optimalization as my bachelors thesis (Facuulty of informatics,
Masaryk's university Brno, Czech Republic), under lead of Yenya
Kasprzak.

Both exportfs and rpc.mount build linked list of exports (shared
functions in export.c). Every time they are inserting new export into
list, they search for same export in list.
I replaced linked list by hash table and functions export_add and
export_lookup by functions hash_export_add and hash_export_lookup
(export.c).

Because some other functions required exportlist as linked list, hash
table has some implementation modification im comparison with ordinary
hash table. It also keeps exports in linked list and has pointer to
head of the list. So there's no need of implementation function
<for_all_in_hash_table>.

Replace existing mount option parser in nfsumount.c with the new pmap
stuffer
function nfs_options2pmap(). Mount option parsing for umount.nfs now
works
the same as it does for mount option rewriting in the text-based
mount.nfs
command.

This adds a number of new features:

1. The new logic supports resolving AF_INET6 server addresses
2. Support is added for the recently introduced "mountaddr" option.
3. Parsing numeric option values is much more careful
4. Option parsing no longer uses xmalloc/xstrdup, so it won't fail
silently if memory can't be allocated
5. Mount program number set in /etc/rpc is respected
6. Mount doesn't exit with EX_USAGE if the hostname lookup fails

umount.nfs command: Add an AF_INET6-capable version of nfs_call_unmount()

We need an AF_INET6-capable version of nfs_call_unmount() to allow the
umount.nfs command to support unmounting NFS servers over IPv6. The
legacy
mount.nfs command still likes to use nfs_call_umount(), so we leave it
in
place and introduce a new API that can take a "struct sockaddr *".

The umount.nfs command will invoke this new API, but we'll leave the
legacy
mount.nfs command and the umount.nfs4 command alone. The umount.nfs4
command does not need this support because NFSv4 unmount operations are
entirely local.

Recently commit 0dcb83a8 changed the po_rightmost() function to
distinguish among several possible mount options by taking a table
containing the alternatives, and returning the table index of the
entry which is rightmost in the mount option string.

If it didn't find any mount option that matches an entry from the
passed-in table, it returned zero. This was the same behavior it had
before, when it only checked for two options at a time. It returned
PO_NEITHER_FOUND, which was zero.

Since this is C, however, zero also happens to be a valid index into
the passed-in array of options.

Modify the po_rightmost() function to return -1 if the entry wasn't
found, and fix up the callers to look for a C-style array index that
starts at zero.

Thanks to Steve Dickson for troubleshooting the problem. His solution
was merely to bump the return value, as callers already expected an
ordinal index instead of a C-style index.

I prefer this equivalent but slightly more extensive change because it
makes the behavior of po_rightmost() more closely match how humans
understand C arrays to work. Let's address some of the confusion that
caused this bug, as well as fixing the run-time behavior.

Now that we have an AF_INET6-capable probe_bothports(), we can support
AF_INET6 when rewriting text-based NFS mount options. This should be
adequate to support NFS transport protocol and version negotiation with
AF_INET6 NFS servers.

all nfs_options2pmap() in nfs_rewrite_mount_options() instead of
open-coding the logic to convert mount options to a pmap struct.
The new nfs_options2pmap() function is more careful about avoiding
invalid mount option values, and handles multiply-specified transport
protocol options correctly.

Sometimes we need to choose the rightmost option among multiple
different mount options. For example, we want to find the rightmost
of "proto," "tcp," and "udp". Or, the rightmost of "vers," "nfsvers,"
"v2," and "v3".

Allow easier testing of nfs-utils in legacy environments by providing
a "configure" option to force the build not to use libtirpc, even if
it's present on the build system. This can also be tried as a
fallback if problems are found with the new TI-RPC-based nfs-utils
code.

Reported by Kevin Coffman and Jonathan Andrews. Apparently --without-uuid
doesn't work with some older versions of autoconf, so correct the help text
to document the option that actually does the trick.

Glibc's getaddrinfo(3) implementation was added over time. Some old
versions support AI_ADDRCONFIG, but don't define it in header files.
Some older versions don't support AI_ADDRCONFIG at all.

Let's add specific checks to configure.ac to see that the local
getaddrinfo(3) implementation is complete. If it isn't, we will make
available a resolver that uses gethostbyname(3) and disable IPv6
entirely.

This patch should apply to 1.1.4 as well as the current nfs-utils repo.
The next patch has a fix for the getaddrinfo(3) call added since 1.1.4
in support/nfs/getport.c.

Revert the patch that added local definitions of AI_ADDRCONFIG and
friends to utils/mount/network.c. While old header versions don't
have those flags, even older versions of getaddrinfo(3) don't
support those flags at all.

Change the priority of "common" log messages so that syslog doesn't get
slammed/spammed when users' credentials expire, or there is another
common
problem which would cause error messages for all context creation
requests.

Note that this will now require that gssd or svcgssd option "-v" is used
to
debug these common cases.

Clients IP address and host names are check on
every RPC request, to both mountd and statd
when TCP wrappers are enabled. To help this
process scale better the access rights are stored
in a hash table, which are hashed per IP address,
RPC program and procudure numbers.

Statd is not unlinking host files during SM_UNMON and
SM_UNMON_ALL calls because the given host is still on the run-time
notify list (rtnl) and the check flag is set when xunlink() is
called. But the next thing the caller of xunlink() does is
remove the host from the rtnl list which means the
unlink will never happen.

So this patch removes the check flag from xunlink() since
its not needed and correctly allocates and frees memory
used by xunlink().

The recv_reply() function was referencing host->ai in a freeaddrinfo(3)
call after it had freed @host.

This is not likely to be harmful in a single-threaded user context,
but it's still bad form, and it will get called out if testing
sm-notify with poisoned free memory. The less noise, the better we
are able to see real problems.

Instead of sending down an infinite expiration value for the rsi(init) and
rsc(context) cache entries, use a reasonable value for the rsi cache, and
the actual context expiration value for the rsc cache.

Prompted by a proposal from Neil Brown as a result of a complaint of a
server running out of kernel memory when under heavy load of rpcsec_gss
traffic. Neil's original patch used one minute for the init cache and one
hour for the context cache. Using the actual expiration time prevents
unnecessary context re-negotiation.

These functions often combine a "struct sockaddr_in" and a "struct pmap" into
a single "clnt_addr_t" argument. Instead of modifying "clnt_addr_t" and all
the legacy code that uses it, I'm going to create a new probe_bothports() API
for the text-based mount command that takes a "struct sockaddr *" and
sockaddr length, and leave the existing probe_bothports() interface, which
takes "clnt_addr_t" arguments, for legacy use.

Update the mount command's probe_port() function to call the new shared
rpcbind query and RPC ping functions. This provides immediate support
for
rpcbind v3/v4 queries, and paves the way for supporting AF_INET6 in the
probe_bothports() path.

Ensure statd gets started if required when non-root
user mounts an NFS filesystem.

The first time an NFS filesystem is mounted, we start statd from
/sbin/mount.nfs. If this first time is a non-root user doing the
mount, (thanks to e.g. the 'users' option in /etc/fstab)
then we need to be sure that the 'setuid' status from mount.nfs
is inherited through to rpc.statd so that it runs as root.

There are two places where we loose our setuid status due to the shell
(/bin/sh) discarding.

1/ mount.nfs uses "system" to run /usr/sbin/start-statd. This runs a
shell which is likely to drop privileges. So change that code to use
'fork' and 'execl' explicitly.
2/ start-statd is a shell script. To convince the shell to allow the
program to run in privileged mode, we need to add a "-p" flag.

We could just call setuid(getuid()) at some appropriate time, and it
might be worth doing that as well, however I think that getting
rid of 'system()' is a good idea and once that is done, the
adding of '-p' is trivial and sufficient.

I have a situation where rpc.gssd appears to not be working.
Mount attempts which need to communicate with it block.

I've narrowed down the problem to that fact that all realtime signals
have been blocked. This means that DNOTIFY_SIGNAL (which is a
realtime signal) is never delivered, so gssd never rescans the
rpc_pipe/nfs directory.

It seems start_kde (or whatever it is called) and all descendants have
these
signals blocked. xfce seems to do the same thing. gnome doesn't.

So if you start rpc.gssd from a terminal window while logged in via
KDE, it doesn't behave as expected.

Introduce a version of nfs_get_mount_client() that supports AF_INET6 and
AF_INET server addresses. If the TI-RPC library is not available when
the showmount command is built, fall back to the legacy RPC user-space
API.

In preparation to support IPv6 in the showmount command, extract the
logic that parses/acquires the target hostname and converts it into an RPC
client handle to contact the remote mountd service, and move it into its
own function.

Have the showmount command invoke the shared nfs_getport() function
instead of its own local version. This gives the showmount command
immediate support for querying via rpcbindv3/v4 in addition to
portmapper, and sets the stage for AF_INET6 support in showmount.

It turns out that at least the mount command and the showmount command
need to query a server's rpcbind daemon. They need to query over
AF_INET6 as well as AF_INET.

libtirpc provides an rpcbind query capability with the rpcb_getaddr(3)
interface, but it takes a hostname and netconfig entry rather than a
sockaddr and a protocol type, and always uses a lengthy timeout. The
former is important to the mount command because it sometimes must
operate using a specific port and IP address rather than depending on
rpcbind and DNS to convert a [hostname, RPC program, netconfig] tuple
to a [socket address, port number, transport protocol] tuple.

The rpcb_getaddr(3) API also always uses a privileged port (at least
for setuid root executables like mount.nfs), which is not required for
an rpcbind query. This can exhaust the local system's reserved port
space quickly.

This patch provides a reserved-port-friendly AF_INET6-capable rpcbind
query C API that can be shared among commands and tools in nfs-utils,
and allows a query to a specified socket address and port rather than
a hostname.

In addition to an rpcbind query interface, this patch also provides a
facility to ping the remote RPC service to ensure that it is operating
as advertised by rpcbind. It's useful to combine an RPC ping with an
rpcbind query because in many cases, components of nfs-utils already
ping an RPC service immediately after receiving a successful GETPORT
result.

There are also a handful of utility routines provided, such as a
functions that can map between [sockaddr, port] and a universal
address.

I've made an attempt to make these new functions build and operate on
systems that do not have libtirpc.

Provide a simple interface that any component of nfs-utils can use to acquire
an RPC CLIENT *. This is an AF_INET6-enabled API, and can also handle
PF_LOCAL sockets if libtirpc is present on the system.

When libtirpc is not available, legacy RPC services will be used instead,
and an attempt to connect to an AF_INET6 address will fail.

The hosts are listed in DNS with proper reverse records, so the reason
why the host is "unknown" isn't clear. This patch just changes the
wording of this error to hopefully make it more clear why the mount
request was rejected. This also makes this error message use a format
more similar to the other error messages in auth_authenticate().

TI-RPC introduced the concept of "netid" which is a string that is
mapped to a set of transport capabilities via a netconfig database.
RPC services register a netid and bindaddr with their local rpcbind
daemon to advertise their ability to support particular transports.

Mike Eisler noted that the use of the term "netid" in nfs(5) is not
appropriate, since Linux does not treat the value of the proto= or
mountproto= options as a netid proper, but rather to select a
particular transport capability provided locally on the client.

The Linux NFS client currently uses a simple internal mapping between
these names and its own transport capabilities rather than using the
names as part of an rpcbind query, thus these strings are really not
netids. They are more akin to what TI-RPC calls "protocol names".

Statd's svc request loop is the only caller of the process_foo()
functions in utils/statd/rmtcall.c, but one of them,
process_notify_list() attempts to invoke statd_get_socket() again.

In today's code, this is unneeded because statd_get_socket() is always
invoked before my_svc_run(). However, if it ever succeeded, it would
get an unprivileged source port anyway, causing the kernel to reject
all subsequent requests from statd.

Thus the process_notify_list() function should not ever call
statd_get_socket() because root privileges have been dropped by this
point, and statd_get_socket() wouldn't get a privileged source port,
causing the kernel to reject all subsequent SM_NOTIFY requests.

So all of the process_foo functions in utils/statd/rmtcall.c should use
the global sockfd instead of a local copy, as it already has a
privileged source port.

I've seen some unexplained behavior where statd starts making calls to
the kernel via an unprivileged port. This could be one way that might
occur.

After some recent discussions, we want to rely on the kernel's network
layer to autotune socket buffers. Since this code is already disabled in
support/nfs/rpcmisc.c (and has been for some time), let's just remove it.

Sometimes in sm-notify, when a system call fails the problem is reported
to stderr but not logged, and then usually sm-notify exits. In cases like
this, there are probably more hosts to notify, but sm-notify dies silently.

Make sure these errors are logged, and that the log messages explain the
nature of the problem.

Also, if sm-notify exits prematurely, make sure this is always reported at
the LOG_ERR level, not at the LOG_WARNING level.

Remove a couple of unnecessary '\n' in the arguments of nsm_log() calls --
nsm_log() already appends an '\n' to the message.